Bulb spraying device



Jan; 21, 1936. J. RUSS] 2,028,355

BULB SPRAYING DEVICE Filed June 7, 1935 B T IfVENTOR ATTORNEY Patented Jan. 21, 1936 UNITED STATES PATENT OFFICE BULB ISPRAYING DEVICE J oseph' Russi,

Peabody,, Mass., assignor to Hy- ,grade Sylvania Corporation, Salem, Mass., a corporation of Massachusetts Application June 7, 1935, Serial No. 25,374 ,8 Claims. (Cl. 91-45) rial t'o a'sharply defined area on the inner wall of a lamp bulba Because of the necessity of maintaining the line of demarcation between the coated and uncoated areas of the bulb, it is important that thespray-jet be very accurate-'- ly controlled, and as pointedout'in the said patent all excess spray material should be divert'ed away from contact with the bulb 'wall. I have found that because of the physical con-" stitution of the translucent material or materials ordinarily used for this purpose, it is important to maintain the uniformity of the spray-nozzle opening, and I have further found that this uniformity is maintained by subjecting the spraynozzle at frequent intervals to'a cleaning op-' eration. Accordingly, one of the principal objects of this invention is to provide a mechanism for spray-coating the inside of a lamp bulb or the like, in conjunction with a spray-gun cleaning device which is automatically operated in timed relation 'to the operation of the spraygun.

A feature of the invention relates to a machine for spraying the interior of lamp bulbs or the like employing a reciprocating v gun, together with a cleaning spray-device for automatically spraying a cleaning fluid on to the nozzle of the spray-gun at regularly recurrent intervals.

A still further feature relates to the mechanism for cleaning a spray-gun of the type disclosed'in said U. S. Patent No. 1,999,014, avoiding the detrimental effects incident to the usual methods of cleaning such as by wiping, brushing, etc. 4

Other features and advantages not specifically' enumerated will be apparent after a consideration of the following descriptions and the appended claims.

In the drawing, Fig. 1 shows in diagrammatic form part of a machine for spraying interiorly a lamp bulb or the like, andembodying features of the invention. s

Fig. 2 is a top plan view in diagrammatic form of Fig. 1 showing more clearly the relation between the spray-gun and the cleaning device according to the invention.

Referring to the drawing the numeral I represents a turntable of any well-known construction such as is widely used in lamp making machinery, it being understoodithat the drawing isessentially schematic in this respect; Table I is rotated intermittently by a shaft 2 through suitable gearing from another main shaft 3.

Mounted for rotation in the table I, are a plu- 'rality of separately rotatable standards 4 carrying uprights 5, 6, which in turn carry spring arms I, 8 to receive and support the lamp bulbs 9 to be sprayed. By suitable gearing (not shown) the members 4 carrying the respective lamp bulbs are rotated about their vertical axes so asto distribute the sprayed material uniformly around the inner surface of the bulb. Inasmuch as the above noted mechanism is well known in the art, further detailed description thereof is not deemed necessary As indicated schematically in Fig. 2,

'table I is provided with'a-plurality of separate positions at which various operations may be effected on the lamp bulbs. Thus in position A the lamp bulbs may be loaded or inserted into the arms 1 and 8, while position B may be the inside spraying position, and succeeding positions C, D, etc., may be employed for heat;- ing, drying, brushing, etc.

Mounted below the table I and at position B is a spray-gun l0 having a spray-nozzle II and an inclined shield I 2. The gun may be connected by a flexible conduit l3 to a reservoir of spray material in liquid or semi-liquid form which material upon being dried on the bulb forms a translucent refractory coating. Also connected to the gun by a flexible conduit I4 is a source of compressed air. For the purpose of controlling the admission of the compressed air to the gun, the latter is provided with a trigger l5 which controls an admission valve (not shown) When the gun is in its retracted or lower position as shown in Fig. 1 this admission valve is closed. For a more detailed description of a spray-gun of the above type, reference may be I had to said U. S. Patent No. 1,999,014.

The spray-gun is adapted to be raised and lowered into and out of each bulb after the bulb is indexed to position B. For this purpose there is shown in schematic form one manner of effecting the desired movement of the spray-gun. The gun may be attached to a lever l6 pivoted at one end at a fixed support I! the lever beingraised and lowered at the proper instant by the cam I8 driven in timed relation to the shaft 2 by any suitable mechanism. When the projection l9 on the lever l6 rides on the high part of cam l8, the spray-gun is raised to the position indicated by the dotted lines. As the gun reaches its spraying position the trigger l5 may engage a fixed projection 20 whereby the compressed air is admitted to the gun, and the coating material is sprayed on to the interior surface of the bulb 9, the coated area being sharply delineated under control of the shield l2 as described in detail in said Patent No. 1,999,014. The spray from the spray-gun is emitted in a fan-like fashion and because of the rotation of the bulb the coating is distributed substantially uniformly over the selected area as determined by the shield l2.

Mounted adjacent the spray-gun and beneath table I is a cleaning mechanism comprising another spray-gun 2| having its discharge nozzle in alignment with the discharge nozzle l2 of gun l0 when the latter is in its lower or retracted position as shown in Fig. 1. Gun 2| is connected by conduit 23 to a source of cleaning fluid 24 preferably water, and also by conduit 25 to a source of compressed air. Gun 2|. is provided -with a trigger or plunger 26 which controls a suitable valve within the gun for admitting the compressed air. For the purpose of controlling the operation of trigger 26 there is provided a cam 21 which is driven in timed relation to cam I8 so that trigger 26 is operated to admit the compressed air only when the spray-gun In is in its lower position, it being understood that the high part of cam 21 is designed to maintain the cleaning jet in an action for any predetermined length of time while the gun I0 is in its lower position. I have found that by projecting a water jet on to the nozzle H, it is possible to completely remove any coating material that would otherwise tend to clog the said nozzle and thus interfere with the accuracy of the coating spray and consequently also interfere with the sharpness of delineation of the coated area on bulb 9, thus entirely avoiding the use of brushes, mechanical wipers, etc., which eventually wear out or destroy the accuracy of the spray-nozzle ll.

As described in said patent, preferably bulb 9 is heated while the spray-gun is acting, and if desired the spray-bulb may be subjected to even further heating and other operations at subsequent positions to which it is indexed by table I. After the bulb is completely dried, it is indexed to the unloading position where it may be removed by any unloading mechanism well known to the art.

Instead of reciprocating the spray-gun H by means of a mechanical lever and instead of operating the spray-gun triggers by mechanical cams, it will be obvious that the spray-gun triggers and the reciprocation of the spray-gun may be effected by solenoids or other electro-mechanical devices in place of the mechanical lever shown, it being understood that the drawing is intended to be merely illustrative in this respect and that various changes and modifications may be made therein without departing from the spirit and scope of the invention. Instead of employing a jet of compressed air'to complete the cleaning of the spray gun, this result may be accomplished by using a steam jet which may be controlled in the proper timed relation in the same manner as the air jet from gun 2|.

What is claimed is:

1. In combination, a gun for spraying the interior of a lamp bulb with a translucent refractory coat, means for bringing said gun and bulb into spraying relation, means for producing a cleaning jet for said spray gun, and means to render said jet effective only when said spray gun is withdrawn from said bulb.

2. In combination, a spray gun for spraying the interior of a lamp bulb with a translucent refractory coat, means for moving said gun from a normal position into spraying position within said bulb, means to produce a cleaning spray, and means to render said cleaning spray effective upon the nozzle of said spray gun only when said spray gun is in its normal position.

3. In combination, a spray gun for spraying the interior of a lamp bulb with a translucent refractory coat, and means to project a cleaning jet upon the nozzle of said gun at regularly recurrent intervals when said gun is removed from said bulb.

4. In combination, a spray gun connected to a supply of coating material and to a supply of compressed air, a cleaning gun connected to a supply of cleaning fluid and to the source of com pressed air, valves for each of said guns to control the spray therefrom, and an interlock arrangement between said valves whereby the cleaning gun is effective to spray the spraying gun nozzle only at predetermined intervals.

5. In a machine of the character described, the combination of means for supporting a lamp bulb, means for rotating said lamp bulb about its axis, a spray gun for coating the interior surface of said bulb, means for reciprocating said spray gun into and out of said lamp bulb, another gun for projecting a cleaning jet upon the nozzle of said spray gun, and means for controlling the operation of said cleaning jet in timed relation to the operation of said spray gun so that said cleaning jet is turned on only when the spray gun is withdrawn from the lamp bulb.

6. In a machine of the character described, the combination of means for supporting a lamp bulb,

a spray gun for spraying the interior of said bulb,

a cam for raising and lowering said spray gun, a cleaning gun for projecting a cleaning jet upon the nozzle of said spray gun, a cam for controlling said cleaning gun and means for operating the.

first cam and the second cam in timed relation so that said cleaning gun is turned on only when the spray gun is withdrawn from the bulb.

'7. In a machine of the character described, the, combination of means for supporting a lamp bulb, means for rotating said bulb about its vertical axis, means for raising and lowering a spray gun into and out of said bulb, a cleaning gun for projecting a cleaning jet upon the nozzle of said spray gun, an air supply for both of said guns, means to render the air supply effective on said spray gun only when said spray gun is in its spraying position, and means for rendering the air supply eifective on said cleaning gun only when said spray gun is in its non-spraying position.

8. In combination, a gun for spraying the interior of a lamp bulb with a translucent refractory coat, means for bringing said gun and bulb into spraying relation, and means for projecting a cleaning jet of steam on the nozzle of said gun only when said gun is withdrawn from said bulb.

JOSEPH RUSSI. 

